A hospital acquired infection (HAI), also known as nosocomial infection, is an infection that is acquired or contracted from a hospital or other medical care facility. The hospital environment can consist of an inpatient or outpatient hospital or surgical center, nursing home, rehabilitation facility, clinic, home healthcare environment or other area of patient care. HAIs may be endogenous, arising from an infectious agent present within a patient's body, or exogenous, transmitted from another source within the hospital or medical care facility. In the United States, the Centers for Disease Control and Prevention (CDC) estimates that nosocomial infections contribute to roughly 100,000 deaths each year from an estimated 1,750,000 HAIs. In addition to patient-to-patient spread, disease transmission may involve medical care staff, personnel, students, visitors, voluntary workers, and the like.
According to the CDC, the most common bacteria associated with nosocomial infections is Staphylococcus aureus. Staphylococcus aureus mutates into an antibiotic resistant strain (MRSA) that is difficult to treat and even regularly mutates into a strain that does not respond to treatment resulting in patient death. The CDC estimates 72,444 patients had invasive MRSA infections in 2014 and 9,194 of those infected patients died as a result. MRSA infection rates may be underestimated because of limited or inaccurate surveillance. MRSA infections now contribute to more deaths than does HIV and its threat level is rising. Various treatments and preventative measures have been trialed; however, there is a concern that use of antibiotic modalities could lead to greater resistance.
Nosocomial infections by Staphylococcus epidermidis (“S. epidermidis”), a less virulent cousin of Staphylococcus aureus, have also gained significant attention due to the ubiquity of the bacterium as a human commensal microorganism. Specifically, S. epidermidis is the most frequently isolated species from human epithelia. While previously regarded as an innocuous skin colonizer, S. epidermidis now represents the most common source of infections on indwelling medical devices. The high rate of infection most likely stems from the fact that S. epidermidis is a permanent part of the human epithelial microflora, resulting in high probability of device contamination during insertion. Although rarely life-threatening, nosocomial infections by S. epidermidis represent a serious burden for the public health system due to their frequency and difficulty of treatment. In the United States alone, an estimated $2 billion is spent annually on costs related to vascular catheter-related bloodstream infections caused by S. epidermidis. Treatment is complicated by specific antibiotic resistance genes and the formation of biofilms, multicellular accumulations that have intrinsic resistance to antibiotics and mechanisms of host defense.
Moreover, nosocomial infections by herpes simplex virus type 1 (“HSV-1”), although relatively infrequent, have also been reported by the medical community. HSV-1 is an enveloped, double-stranded DNA virus commonly known as a “cold sore.” HSV-1 is usually acquired through direct contact with infected lesions, sores, and/or oral secretions, such as through kissing or sharing drinking glasses with an infected individual. While infection is mostly asymptomatic, symptoms of the virus include painful blisters or open sores in the skin or mucous membranes of the mouth, lips or genitals. Currently, there is no cure for HSV-1; it persists in the body by becoming latent and concealing itself in the cell bodies of neurons. Some carriers of the virus will continue to experience episodes of viral reactivation or outbreaks, where virus replication and shedding occurs and causes new sores to appear on the skin. HSV-1 is common worldwide, and it is estimated that the majority of United States citizens are exposed to or infected by HSV-1 by the time they reach adolescence.
Current methods of preventing nosocomial infectious outbreaks in a health care environment include continued education for staff, strict adherence to infection control protocols, and early detection and communication of nosocomial infection events. Nevertheless, the current methods have several limitations in their ability to provide immediate protection to patients and medical staff alike. The treatment modality, described herein, provides a means to successfully eliminate bacteria that causes nosocomial infections preoperatively and postoperatively. The treatment can eliminate the target bacteria before an infection has occurred and also eliminate the bacteria causing an ongoing infection.